Mod dashboard: more data than for today

[astyled]

Apparently, the dashboard only shows data for that day for the UTC0 timezone. This makes it quite useless to monitor additions, since to see them the dashboard should be checked at ~23:58 UTC0. 24 hours is quite small range. With our mod activity it is easily possible to miss the additions, and it would be better to increase the range, maybe add an ability to limit the range. Tolerating local timezone will not make much sense in this case, so it's not that necessarily.